Merge samba.org:/stuff/paulus/kernel/linux-2.5

into samba.org:/stuff/paulus/kernel/for-linus-ppc

arch/ppc/kernel/entry.S

@@ -173,8 +173,10 @@ _GLOBAL(DoSyscall)
 	cmpli	0,r0,NR_syscalls
 	bge-	66f
 	rlwinm	r10,r1,0,0,18	/* current_thread_info() */
-	lwz	r10,TI_FLAGS(r10)
-	andi.	r10,r10,_TIF_SYSCALL_TRACE
+	lwz	r11,TI_FLAGS(r10)
+	rlwinm	r11,r11,0,~_TIF_FORCE_NOERROR
+	stw	r11,TI_FLAGS(r10)
+	andi.	r11,r11,_TIF_SYSCALL_TRACE
 	bne-	syscall_dotrace
 syscall_dotrace_cont:
 	lis	r10,sys_call_table@h
@@ -192,7 +194,11 @@ ret_from_syscall:
 	mr	r6,r3
 	li	r11,-_LAST_ERRNO
 	cmpl	0,r3,r11
+	rlwinm	r12,r1,0,0,18	/* current_thread_info() */
 	blt+	30f
+	lwz	r11,TI_FLAGS(r12)
+	andi.	r11,r11,_TIF_FORCE_NOERROR
+	bne	30f
 	neg	r3,r3
 	cmpi	0,r3,ERESTARTNOHAND
 	bne	22f
@@ -205,7 +211,6 @@ ret_from_syscall:
 30:	LOAD_MSR_KERNEL(r10,MSR_KERNEL)	/* doesn't include MSR_EE */
 	SYNC
 	MTMSRD(r10)
-	rlwinm	r12,r1,0,0,18	/* current_thread_info() */
 	lwz	r9,TI_FLAGS(r12)
 	andi.	r0,r9,(_TIF_SYSCALL_TRACE|_TIF_SIGPENDING|_TIF_NEED_RESCHED)
 	bne-	syscall_exit_work

include/asm-ppc/ptrace.h

@@ -49,6 +49,8 @@ struct pt_regs {
 #define instruction_pointer(regs) ((regs)->nip)
 #define user_mode(regs) (((regs)->msr & MSR_PR) != 0)
 
+#define force_successful_syscall_return()   set_thread_flag(TIF_FORCE_NOERROR)
+
 /*
  * We use the least-significant bit of the trap field to indicate
  * whether we have saved the full set of registers, or only a

include/asm-ppc/thread_info.h

@@ -86,6 +86,8 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
 #define TIF_POLLING_NRFLAG	4	/* true if poll_idle() is polling
 					   TIF_NEED_RESCHED */
+#define TIF_FORCE_NOERROR	5	/* don't return error from current
+					   syscall even if result < 0 */
 
 /* as above, but as bit values */
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
@@ -93,6 +95,7 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
+#define _TIF_FORCE_NOERROR	(1<<TIF_FORCE_NOERROR)
 
 #endif /* __KERNEL__ */